Your decision to not have recess was okay, but you went too far to tell them that you knew who did it and if the person didn't confess, there would be more consequences. That put you in trouble because a)you really don't know and b) you have no way of following up what you said. You should have just left it at no recess for that particular day.
It is possible that the person wasn't looking and accidentally kicked the juice container, spilling it without realizing it.
I think you would do better to tell the children that you were overly tired that day and that the recess consequence was enough for that day. You should tell them that you want them to be much more careful about food and drink in the classroom. Make it one of your rules that you post, and emphasize this is a school rule. You can also put four kids in charge of helping to keep certain areas in the classroom clean and give them points for doing that. Get a routine going where every hour or so you stop to put some books or papers away and check under the desks, etc.
It is your room-- and you can help the students learn to keep their area neat and clean.
In the future, instead of missing the whole recess (who does that actually punish-- you or them??),
maybe make them wait one minute for each scrap of garbage left on the floor. That is a concrete thing they can relate to and it will give them the message and keep the area clean-- especially if you have four helpers who are getting points on their participation grade for helping to maintain cleanliness as a value for the class.
Hugs to you... Take a break and enjoy your Thanksgiving.
Also, find a veteran teacher whose classroom you like and whose teaching style you respect who works in the same building. That person will let you know what how far the administration will back you up and where they might draw the line.
Be careful, too, of making consequences when you are angry-- especially of consequences you can't enforce.
They must respect your authority (which is there ultimately in order that they can become the most successful learners possible) and agree to follow your class rules-- but don't demand perfection from them about everything. Steadily praise improvement and find ways to encourage them.
Love,
A fellow teacher